A pilot implementation of a text only system
was undertaken using X11 R3, and the Athena
Widget library, on a set of Unix workstations (from various different
vendors: one advantage of the choice of X is its machine
independence). The star (shared memory) model was used; a single process
runs the conference with X protocol connections to each display.
An example of the actual user interface is shown later in the chapter.
Some simplifications were found to be necessary after some experience
with several users:

Rate
Changing the layout as the speaker changes is unsatisfactory.

Complexity
Too much clutter for expressing illocutionary acts.

Quality
A 19 inch monitor isn't big enough!

The current implementation includes the Valve to allow floor
control, but none of the rich floor control mechanisms have yet been
implemented. These will be added.
Reports from users are that floor control is definitely required when
more than two users are present. The main reason quoted is simply to
limit the amount of text appearing at once.